1. Technical Field
The present invention relates to a liquid ejecting head and a liquid ejecting apparatus which eject a liquid from a nozzle opening, and in particular, to an ink jet type recording head and an ink jet type recording apparatus which discharge ink as the liquid.
2. Related Art
An ink jet type recording head which is an example of a liquid ejecting head is provided with a piezoelectric actuator on one side of a flow channel formation substrate on which a pressure generation chamber, which is in communication with a nozzle opening, is provided, and ink droplets are discharged from the nozzle opening by generating a pressure change in ink inside the pressure generation chamber through driving of the piezoelectric actuator.
Lead-out wiring is led out from an electrode of the piezoelectric actuator that is provided on a side of the flow channel formation substrate to the top of a surface side of the flow channel formation substrate, and connection wiring that is connected to a driving circuit or the like is connected to the lead-out wiring (for example, refer to Japanese Patent No. 4877481).
This kind of wiring that is led to the top of a flow channel formation substrate is configured by laminating an adhesive layer and a conductive layer in order to improve adhesion with the piezoelectric actuator and adhesion with a surface side of the flow channel formation substrate.
However, there is a problem that there is a concern that metals that are ionized with most ease will be eluted when a voltage is applied to the lead-out wiring, and the wiring will short-circuit with adjacent wiring. In particular, in a case in which the lead-out wiring is formed with a high density due to a trend for increases in the density of piezoelectric actuators, an interval between mutually adjacent lead-out wiring is narrower, and it is more likely that a so-called leak path that short-circuits due to eluted materials will be formed. In addition, since a movement speed of ionized metals is proportional to field intensity, field intensity is higher due to the lead-out wiring being formed with a high density, and a leak path is formed in a short time.
In addition, there is a problem that if an adhesive layer is provided in the lead-out wiring, the adhesive strength of the lead-out wiring is reduced, and it becomes more likely that the lead-out wiring will peel.
Additionally, these kinds of problems are not limited to ink jet type recording heads, and are also found in liquid ejecting heads that eject other liquids.